php - 我可以将这两个查询合并到一个查询中吗

Question

你好，我可以将这两个查询合并到一个查询中吗？我的第一个查询获取数据库中的文章数量，第二个查询获取所有文章的所有访问的总和什么是使其成为一个查询的最佳方法

$stmt = $db->query('SELECT * FROM stories');
$story_count = $stmt->rowCount();

$stmt = $db->query("SELECT sum(visits) FROM stories");
$total_visits = $stmt->fetchColumn();

Answer 1

试试喜欢

$stmt = $db->query('SELECT COUNT(*) as total_cnt,
                   SUM(visits) as total_visits FROM stories');

然后执行您的查询，您将从“total_cnt”和“total_visits”获得结果

Answer 2

SELECT COUNT(*) as total, SUM(visits) as total_visits FROM stories;

Answer 3

SELECT Story.*, COUNT(*) as total, SUM(Story.visits) as total_visits FROM stories AS Story;

如果您想获得其他字段SUM并COUNT使用.*.

Answer 4

是的，试试这个：

$stmt = $db->query('SELECT count(*),sum(visits) FROM stories');
$result = $stmt->fetch_array(MYSQLI_NUM);
$story_count = $result[0];
$total_visits = $result[1];